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A strap-on rescue backpack developed by Russian space engineers would help a person jump from danger and glide safely to the ground inside an inflatable umbrella, its creators say.

The device is inspired by an inflatable nose-cone initially designed for a Russian probe to Mars but was never used.

The original will be tested in a souped-up form in a missile launch next month.

"The idea is to have a rescue pack that is affordable and easy to use," says a spokesperson for Lavochkin Association, a subsidiary of Russia's Federal Space Agency, which is searching for investors to complete and market the product.

In an emergency, such as being trapped in a burning skyscraper, the user would strap on the backpack.

He or she would then sit on a window ledge with the pack facing outwards, pull a ring to inflate the device and tumble backwards.

The gadget instantly unfolds into a shallow cone, rather like a huge umbrella without a handle some 7 metres across, braced by inflatable spokes and an inflatable outer ring.

The user then glides to Earth, strapped to a shell at the centre of the cone, with small airbags dampening the final descent.

"So far, we have tested it at heights from 15 metres to 110 metres using a half-sized human dummy weighing 40 kilograms and a package of sensors," the spokesperson says.

At the limit

The deceleration in the last 0.5 seconds of descent is less than 12 G, he says, or 12 times the force of gravity.

This is just below the US military's 12.1 G threshold of what constitutes a 'reasonable risk' of injury for a paratrooper.

That figure applies to a young, healthy adult of around 80 kilograms, not a small adult or a child.

But cervical and internal injuries are more likely if the body is in a vertical position at impact rather than a horizontal one.

The Moscow-based company is looking for funds to complete the test program and, if the results are satisfactory, market the rescue pack, which would sell for around US$1500 (A$2000) apiece.

Inspired by a space probe

The idea comes from an inflatable nose-cone developed for Russia's Mars 96 space probe.

The device was designed to brake the probe's descent through the planet's carbon dioxide atmosphere and help it to glide to the ground.

But the probe was lost due to a booster failure at launch and the gadget was never used.